Temperature and method experience of BGA welding

First of all, if glue is applied to the four corners of the chip and around the chip, first adjust the temperature of the hot-air gun to 330 degrees and the wind force to the minimum. Hold the gun in your left hand and tweezers in your right hand. While blowing, you can pick up the glue with tweezers. Both white glue and red glue can be removed in a short time. Pay attention to the time when you do it and the time when you blow it
It can’t be too long. The temperature of biting is high. You can do it intermittently. Do it for a while, stop for a while. In addition, when picking with tweezers, you should also be careful. The glue is not softened and you can’t pick with strength. You should also be careful not to scratch the circuit board. If possible, you may also use glue to soften the glue, but I think you still use hot-air gun BGA welding come soon.

Let’s talk about the whole steps of making BGA repair bench. I can basically succeed in making BGA repair bench in this way, and point drop rarely occurs. Let’s take redo graphics card as an example.
Let’s talk about my steps in BGA:
1. First, add an appropriate amount of high-quality BGA Solder Paste around the graphics card, set the temperature of the hot air gun to 200 degrees, minimize the wind force, blow against the solder paste, and slowly blow the solder paste into the graphics card chip. After the solder paste around the graphics card chip is blown under the chip, adjust the wind force of the hot air gun to the maximum and face the chip again
The purpose of this is to make the solder paste deeper into the chip.

Temperature and method experience of BGA welding
2. After the above steps are completed, wait for the chip to cool down completely (very important), and then wipe the excess solder paste on and around the graphics card chip with alcohol cotton. Be sure to wipe it clean.
3. Then, tin platinum paper is pasted around the chip. In order to ensure that the high temperature during welding will not damage the capacitor, field tube and triode around the graphics card, and the crystal oscillator, especially the video memory around the graphics card, the tin platinum paper should be pasted to 15 layers during Beiqiao. My tin platinum paper is thin, and I don’t know how good the thermal insulation effect is when 15 layers of tin platinum paper are pasted,
But it must work. At least every time when doing BGA, there was no problem with the video memory next to the graphics card and the North Bridge, and it was not welded and exploded.

Temperature and method experience of BGA welding
If the BGA repair platform for graphics card is still not lit after it is completed, I can be sure that it is not completed. I won’t doubt whether the next video memory or North Bridge is damaged. On the back of the graphics card chip, tin platinum paper should also be pasted. I usually stick it to the fifth floor. And the area is slightly larger. This is to prevent when making BGA repair bench
, the small objects on the back of the chip fall off when heated. Sticking multiple layers is better than sticking one layer. If you stick one layer, the high temperature will completely melt the glue on the tin paper and stick it to the board, which is very ugly. If you stick multiple layers, this phenomenon will not appear.